Method of steam treating textured yarn



y 1969 H. M. STRUB, JR 3,453,817

I METHOD OF STEAM TREATING TEXTURED YARN Filed Nov. 5. 1964 T 35 T 55 y 52 )5 5\ 4 Z; 40 4\ Y i 42 C l2 6O 5L 7O 26 z\ 64 5 V mvsmoa: HENRY MICHAEL ST2U15,J2.

ATTORNEYS United States Patent 3,453,817 METHOD OF STEAM TREATING TEXTURED YARN Henry Michael Strub, Jr., Winston-Salem, N.C., assignor to The Duplan Corporation, Winston-Salem, N.C., a corporation of Delaware Filed Nov. 5, 1964, Ser. No. 409,226 Int. Cl. D02g 3/24, 1/16, 1/20 US. Cl. 57-157 6 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to an improved method of steam treating a textured thermoplastic yarn and more particularly to a steam treating method wherein the textured multifilament yarn is passed through a steam zone in a partially relaxed condition to cause the yarn to contract and to develop the latent crimp in the yarn uniformly. The yarn is then wound into a soft or loose takeup package that may :be uniformly dyed and/or heat-set to stabilize the yarn in the partially relaxed condition.

The term textured is used herein to describe thermoplastic yarns that have been processed by any one of several well-known methods to impart crimps, curls or loops thereto. For example, it is well known that stretch and bulk characteristics can be imparted to continuous multifilament yarns by heat-setting and then twisting, false twisting with heat, gear crimping, blade curling, passing the yarn through a heated stuffer box, and passing the yarn through a jet of air.

A primary object of the present invention is to provide an improved method for producing a textured thermoplastic yarn having regulated and controlled physical characteristics that are uniform throughout its length.

More specifically, the present steam treating method provides means for uniformly partially relaxing the textured thermoplastic yarn while simultaneously subjecting the partially relaxed textured yarn to a steam treatment so that the latent crimping, curling or looping characteristics in the yarn may be activated or developed to any desired degree and wherein the steam treatment causes a uniform supenbulking of the yarns as the crimps in the individual filaments are thrown out of phase with the crimps in adjacent filaments.

The method of the present invention is carried out on an apparatus of the type in which feed roll means is provided for withdrawing the textured yarn from a supply package at a predetermined rate, take-up roll means is provided for taking up the textured yarn at a rate less than the predetermined feed roll rate so that the degree of relaxation of the textured yarn may be accurately controlled as it passes from the feed roll means to the take-up roll means, and a steam treating zone is provided between the feed roll means and the take-up roll means and through which the textured and partially relaxed yarn passes. The moist heat of the steam treating zone causes the uniform activation and development of the desired degree of the latent crimping characteristics of the yarn, in accordance with the degree of relaxation of the yarn as it passes through the steam zone.

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The steam treating zone includes a chamber in the form of an elongate tube through which the yarn is passed. The tube has an open upper end and a substantially closed lower end with an upstanding collar extending up inside of the tube and closely surrounding the yarn as it initially enters the tube. A steam inlet connection is provided adjacent the lower end of the tube and disposed at substantially the level of the upper end of the upstanding collar for projecting steam into the tube. The steam moves up the tube and passes out of the open upper end and any condensation formed within the tube will flow down to the lower end of the tube and around the upstanding collar where it is removed through a drain line connected thereto.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmentary vertical sectional view through the steam treating apparatus and showing one treating station;

FIGURE 2 is a fragmentary front elevation of the steam treating station shown in FIGURE 1, looking inwardly from the left-hand side thereof;

FIGURE 3 is an enlarged fragmentary front elevation of the steam treating chamber;

FIGURE 4 is a sectional plan view taken substantially along the line 4-4 in FIGURE 3; and

FIGURE 5 is an enlarged fragmentary vertical sectional view through the lower portion of the steam chamber, taken substantially along the line 55 in FIGURE 4.

As shown in FIGURES 1 and 2, the steam treating apparatus includes spaced apart frame stands .10, only one of which is shown, that are connected together and supported by suitable longitudinal frarne members including a lower rail 11, an intermediate rail 12 and an upper rail 13. The steam treating apparatus preferably has spaced steam treating stations along each side, although only one side of the apparatus and only one steam treating station is shown.

First feed means, broadly indicated at 20, is supported on the intermediate rail 12. The first feed means 20 includes a pair of feed rolls 21 and 22 around which the textured yarn Y is wound. The feed rolls 21, 22 are normally set at a slight angle to cause the yarn to advance thereon. The feed rolls 21, 22 are driven by means of suitable gears, not shown, in the housing of the feed roll means 20 and a drive gear 23 which is fixed on a drive shaft 24. The drive shaft 24 is supported for rotation in the frame stand 10. A clutch lever 25 (FIGURE 2) is provided on the front of the housing of the feed roll means 20 and maybe operated to stop and start rotation of the feed rolls 21, 22 when desired. The feed rolls 21, 22 withdraw the textured yarn Y from a supply package S and through a yarn guide 26 at a predetermined rate.

The textured yarn Y moves upwardly from the feed roll 21 and passes through a substantially C-shaped ceramic yarn guide 30 which is fixed on the rail 12 (FIG- URES 3 and 4). The yarn Y then passes through the steam treating chamber, broadly referred to at C, over a yarn guide rod 31, through a travese yarn guide 32 and is wound onto the take-up package T. The take-up package T is formed on a tube 33 that is supported on a mandrel 33a which is in turn supported for rotation in one end on the forward end of a support arm 34. The rear end of the support arm 34 is pivotally supported as at 35 (FIGURE 1) in the upper end of a support block 36. The lower end of the support block 36 is suitably secured to the upper rail 13.

As the yarn Y is wound onto the take-up package T, the take-up package is rotated by means of a cork drive roll 40 which is in turn fixed on a drive shaft 41. The forward end of the support arm 34 may be raised to move the take-up package T out of driving engagement with the cork drive roll 40 and hold the same in the raised inoperative position by a support lever 42, the upper end of which is suitably connected to the forward end of the support arm 34. The cork drive roll 40 and the takeup package T form a second feed means or a take-up roll means that provides a constant take-up speed for the yarn Y.

The yarn is wound onto the package T at a slower rate than it is withdrawn from the supply package S by the feed rolls 21, 22 so that the yarn is at least partially relaxed as it moves between the feed roll 21 and the take-up package T. The relative rotational speeds of the drive shafts 23 and 41 can be varied within a wide range so that the amount of overfeed or the degree of relaxation of the yarn Y can be accurately and uniformly controlled.

As best shown in FIGURES 3-5, the steam chamber C includes a tubular housing 50 that is supported in upright position by means of a collar 51 which is fixed on the upper end of a Z-shaped support bracket 52 that is in turn suitably supported at its lower end on the intermediate rail 12. The tubular housing 50 is preferably about six inches long, has a one inch outside diameter and a wall thickness of about inch. The upper end of the tubular housing 50 is open and terminates a short distance above the collar 51. However, as shown in dashdot lines at 50a in FIGURE 2, the upper end of the tubular housing may extend upwardly a greater distance and may be flared outwardly, if desired. The lower end of the tubular housing 50 is substantially closed by a plug 54 (FIGURE which has an upstanding collar portion 55 and a yarn passageway 56 extending therethrough. The collar 55 preferably extends upwardly into the tubular housing 50 a distance of about inch.

A steam inlet opening 60 (FIGURE 5) is provided in the lower portion of the tubular housing 50 and at substantially the level of the upper end of the collar 55. One end of a pipe fitting 61 is connected to the inlet opening 60 and its other end in connected to one side of a manually operable cut-off valve 62. The other side of the cut-off valve 62 has one end of a steam branch line 63 connected thereto and its other end is connected by a T-connection 64 to a main line 65 (FIGURE 1).

A condensation outlet opening 66 (FIGURE 5) is provided at the lower end of the housing 50. The condensation outlet or opening 66 is communicatively connected with one end of a drain branch line 70. The other end of the drain branch line 70 is connected to a main drain pipe 71 (FIGURE 1). The steam preferably enters the opening 60 and the tubular housing 50 under a pressure of from about 5 to pounds and escapes at the open upper end of the tubular housing 50. As illustrated in FIGURES 1 and 2, the escaping steam surrounds the yarn Y for some distance after it passes out of the tubular housing 50. Thus, the steam treating zone extends from the bottom of the tubular housing 50 to a point almost up to the guide rod 31.

The heat and moisture of the steam, surrounding the partially relaxed textured yarn Y, causes the latent crimped, curled or looped characteristics of the yarn to be activated or developed. in accordance with the degree to which the yarn is relaxed or overfed while it passes through the steam treatment zone. The temperature within the steam chamber C is maintained at about 212 F. and while this temperature is not sufficiently high to set the developed crimp in the textured yarn, it does cause the latent stresses in the yarn to quickly develop and to remain in the yarn as it is wound onto the take-up package T in partially relaxed condition.

The amount or degree of relaxation of the textured yarn, as it passes through the steam treating zone, may be varied as desired and in most cases is determined by the end result desired and the manner in which the latent crimp was produced in the textured yarn. For example, when it is desired to dye a false twisted yarn directly, the take-up package T is formed with an overfeed of about to percent. On the other hand, a soft take-up package that is suitable for direct dyeing can be formed of textralized yarn (yarn that has been passed through a heated stuffer crimping box) with an overfeed of about 20 to 35 percent. However, when false twisted yarn is to be subsequently stabilized or heat-set, as in an autoclave with steam under pressure, the take-up package is formed with an overfeed of about 10 to 35 percent.

Several different types of thermoplastic multifilament textured yarns have been processed in accordance with the present steam treating method and apparatus and in some cases the take-up package has been directly dyed while in other cases the takeup package has been heatset to stabilize the activated crimp in the yarn. The yarns steam treated in accordance with this invention can be used for knitting or weaving. It is preferred, particularly when steam treating false twisted yarn, first to ply one end of S torque yarn with one end of Z torque yarn to provide a plied textured yarn with balanced torque. Then, the balanced torque yarn is withdrawn from the supply package S and passed through the steam treating apparatus.

By controlling the percentage of relaxation of the yarn while it is steamed, various physical characteristics of the yarn may be developed to suit the particular end use of the yarn. The details of the invention will be better understood by reference to the following examples of yarns that have been steam treated. While the processing yarns of 70 to denier is described, it is to be understood that the present invention is not limited to the particular yarns set forth in these examples and can be used to treat yarns of any desired denier.

EXAMPLE I Two ends of 100 denier 34 filament oppositely false twisted nylon are plied together with two turns per inch of ply twist and then processed on the apparatus of this invention. In this particular instance, the feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 798 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 433 feet per minute. Thus, the yarn is overfed 85 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The treated yarn is wound on the take-up package T in sufficiently loose condition so that, if desired, it can be uniformly dyed throughout its length in a direct package dyeing operation and while still wound on the take-up package. In this case, the take-up tube 33 would be perforated. However, it is preferred that the take-up tube 33 be removed and the muff of relaxed yarn be placed on the spindle of a conventional package dyeing machine.

EXAMPLE II Two ends of 70 denier 34 filament oppositely false twisted nylon are plied together with two turns per inch of ply twist. This yarn is then processed on the apparatus of this invention in the same manner as in Example I and subsequently dyed.

EXAMPLE III Two ends of 70 denier 17 filament oppositely false twisted nylon are plied together with three turns per inch of ply twist and then processed on the apparatus of this invention. The feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 6 50 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 300 feet per minute. Thus, the yarn is overfed 117 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The steam treated yarn is wound on the take-up package T in sufficiently loose condition so that it can be uniformly dyed throughout its length in a direct dyeing operation and while still wound on the take-up package.

EXAMPLE IV Two ends of 70 denier 17 filament oppositely false twisted nylon are plied together with two turns per inch of ply twist and then processed on the apparatus of this invention in the same manner as the yarn in Example III.

EXAMPLE V Two ends of 100 denier 50 filament nylon that have been processed through a stuffer crimping box are plied together with two turns per inch of ply twist and then processed on the apparatus of this invention. The feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 650 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 534- feet per minute. Thus, the yarn is overfed 21 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The treated yarn is wound on the take-up package T in sufiiciently loose condition so that it can be uniformly dyed throughout its length in a direct dyeing operation and while still wound on the take-up package.

EXAMPLE VI Two ends of 140 denier 68 filament nylon that have been processed by passing the same through a stuifer crimping box are plied together with two turns per inch of ply twist and then processed in the same manner as the yarn of Example V.

EXAMPLE VII Three ends of 70 denier 34 filament nylon yarns that each have been processed on a stuifer crimping box are plied together with two turns per inch of ply twist and processed on the apparatus of this invention. The feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 650 feet per minute While the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at the rate of 520 feet per minute. Thus, the yarn is overfed 25 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The treated yarn is wound on the take-up package T in sufficiently loose condition so that it may be uniformly dyed throughout its length in a direct dyeing operation and while wound on a perforated take-up tube.

EXAMPLE VIII Two ends of 70 denier 34 filament oppositely false twisted Dacron are plied together with two turns per inch of ply twist and then processed on the .apparatus of this invention. The feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 650 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 534 feet per minute. Thus, the yarn is overfed 22 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The treated yarn is wound on the take-up package T in sufficiently loose condition so that it can be uniformly stabilized or heat-set throughout its length while still wound on the take-up package. The take-up package is preferably stabilized by the use of steam and pressure, such as in an autoclave.

EXAMPLE IX Two ends of 70 denier 34 filament oppositely false twisted nylon are plied together with two turns per inch of ply twist and then processed on the apparatus of this invention. In this particular instance, the feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package at a rate of 650 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 480 feet per minute. Thus, the yarn is overfed 35 percent as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The steam treated yarn is wound onto the take-up package T in sufficiently loose condition so that it can be uniformly steam stabilized in the same manner as the yarn of Example VIII.

EXAMPLE X Two ends of 70 denier 14 filament oppositely false twisted Dacron are plied together with two turns per inch of ply twist and then processed on the apparatus of this invention. The feed rolls 21, 22 are rotated to withdraw the yarn Y from the supply package S at a rate of 650 feet per minute while the cork take-up roll 40 is rotated to wind the yarn onto the take-up package T at a rate of 585 feet per minute. Thus, the yarn is overfed 11 percent as it passes through the steam chamber C. The latent crimp in the partially relaxed yarn is activated and developed as it passes through the steam chamber C and it contracts lengthwise so that it is uniformly wound to form a soft take-up package T. The treated yarn is wound on the take-up package T in suificiently loose condition so that it can be uniformly steam stabilized in the same manner as the yarn of Examples VIII and IX.

Since all of the yarns in the above examples are overfed so that they are in partially relaxed condition when they are subjected to the steam treatment, the latent crimping characteristics of the yarns are activated so that they become somewhat more bulky than they were before the steam treating process. Generally, the textured yarn is overfed from about 10 to percent and the amount of bulking of the yarn is determined by the amount of overfeeding and the type of textured yarn that is being processed. This overfeed is accomplished by rotating the cork drive roll 40 to wind the yarn on the package T at a slower linear speed than it is withdrawn from the supply package S by the feed rolls 21, 22. In any event, the steam treated yarn has an amazing uniformity throughout its length. The dyed yarns of Examples I through VII have a uniform color throughout their length and the steam stabilized yarns of Examples VIII through X have uniform elasticity and bulkiness throughout their length.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not only for purposes of limitation, the scope of the invention being defined in the claims.

I claim: 1. A method of producing a bulky textured multifila ment thermoplastic yarn comprising the steps of:

(a) continuously withdrawing the textured yarn from a supply package at a predetermined rate of speed,

(b) winding the textured yarn onto a take-up package at a lesser speed than said predetermined speed to partially relax the yarn after it is withdrawn from the supply package,

(c) first passing the partially relaxed yarn through a steam chamber wherein the steam is confined to an area closely surrounding the moving yarn, and immediately thereafter,

(d) passing the partially relaxed yarn through a zone of unconfined steam, directed outwardly from said steam chamber and in the direction of travel of the yarn, the length of travel of the yarn through the Zone of unconfined steam being at least as great as the length of travel of the yarn through the steam chamber, the successive passage of the partially relaxed yarn through the steam chamber and the steam zone uniformly developing the latent crimp therein and causing the yarn to contract and bulk before being wound on the take-up package in the con tracted condition.

2. A method according to claim 1 wherein the predetermined withdrawal speed is Within the range of about 10 to 20 percent greater than the wind-up speed.

3. A method according to claim 1 including the additional steps of false twisting two ends of multifilament thermoplastic yarn in opposite directions, and then plying the oppositely false twisted yarn ends together to form the supply package from which the textured yarn is withdrawn in step (a).

4. A method according to claim 3 wherein the oppositely twisted ends of multifilament thermoplastic yarn are in the range of about 70 to 140 denier, and wherein the predetermined withdrawal speed is within the range of about 10 to 120 percent greater than the wind-up speed.

5. A method according to claim 1 including the additional step of dyeing the bulky textured yarn while still wound on the take-up package formed in step (d).

6. A method according to claim 1 including the additional step of heat setting the bulky textured yarn while still wound on the take-up package formed in step (d).

References Cited UNITED STATES PATENTS 3,003,222 10/1961 Pitzel 2872 3,022,565 2/1962 Fitzgerald 2872 3,063,124 11/1962 Hilleary et al. 5734 3,077,724 2/1963 Stoddard et a1 5'7157 3,099,064 7/1963 Haynes. 3,106,725 10/1963 Stiner et al 8-1551 3,131,528 5/1964 Scragg 57-157 XR 3,145,398 8/1964 Wyatt 8-155.1 3,165,881 1/1965 De Moncuit et al 57-34 3,310,857 3/1967 Loftin et al. 57157 XR FOREIGN PATENTS 850,693 10/1960 Great Britain. 787,619 12/1957 Great Britain.

STANLEY N. GILREATH, Primary Examiner.

W. H. SCHROEDER, Assistant Examiner.

US. Cl. X.R. 

